title: Use of Entero-Test, a simple approach for non-invasive clinical evaluation of the biliary disposition of drugs.
abstract: OBJECTIVE
  To evaluate the non-invasive collection of bile from healthy human subjects for the qualitative characterization of the biliary disposition of a drug, using spectrometric techniques.
  
  
  METHODS
  Twenty subjects underwent non-invasive bile capture using a peroral string test (Entero-Test) device prior to and following a single oral dose of simvastatin (80 mg). The device, consisting of a weighted gelatin capsule containing a highly absorbent nylon string, was swallowed by each subject with the proximal end of the string taped to the face. Once the weighted string was judged to have reached the duodenum, gallbladder contraction was stimulated in order to release bile. The string was then retrieved via the mouth, and bile samples were analysed for drug-related material using spectrometric and spectroscopic techniques following solvent extraction.
  
  
  RESULTS
  Numerous metabolites of simvastatin were detected, and the major metabolites were consistent with those reported from studies where bile was collected using invasive techniques from patients dosed with [(14) C]-simvastatin.
  
  
  CONCLUSIONS
  The results from this study demonstrate the utility of deploying the Entero-Test in human studies to provide structural information on biliary metabolites. This can be readily applied in drug development studies, including those in the target patient population and may eliminate the need for more invasive sampling techniques.
authors.affiliation: Toxicokinetics and Biotransformation, DMPK, Platform Technology and Science Department, GlaxoSmithKline, Park Road,Ware, Hertfordshire SG12 0DP, UK. william.guiney@gsk.com
authors.forename: William J
authors.initials: WJ
authors.lastname: Guiney
authors.forename: Claire
authors.initials: C
authors.lastname: Beaumont
authors.forename: Steve R
authors.initials: SR
authors.lastname: Thomas
authors.forename: Darren C
authors.initials: DC
authors.lastname: Robertson
authors.forename: Simon M
authors.initials: SM
authors.lastname: McHugh
authors.forename: Annelize
authors.initials: A
authors.lastname: Koch
authors.forename: Duncan
authors.initials: D
authors.lastname: Richards
mesh_terms: D000328:Adult; D000924:Anticholesteremic Agents / Q000032:analysis / Q000378:metabolism*; D001646:Bile / Q000378:metabolism*; D001647:Bile Acids and Salts / Q000032:analysis / Q000378:metabolism*; D001659:Biliary Tract / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D004764:Enterohepatic Circulation; D005260:Female; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D004364:Pharmaceutical Preparations / Q000032:analysis / Q000378:metabolism*; D011933:Reagent Kits, Diagnostic; D012016:Reference Values; D019821:Simvastatin / Q000032:analysis / Q000378:metabolism*
chemical_list: D000924:Anticholesteremic Agents; D001647:Bile Acids and Salts; D004364:Pharmaceutical Preparations; D011933:Reagent Kits, Diagnostic; D019821:Simvastatin